Guaranteeing QoS in Bluetooth Scatternet Sensor Network

Bluetooth is a low power and cost-effective short range wireless network technology working in 2.4GHz ISM band. Bluetooth can be implemented either in piconet or Scatternet. In piconet the devices can communicate with each other forming a network with maximum of 8 nodes (1 master and 7 slaves). Two or more piconets can be connected through a common Bluetooth device (a gateway or bridge) to form a Scatternet. But the difficult thing is to achieve Quality of service (QoS) in Bluetooth particularly in the Scatternet. Quality of service refers to the efficient management of system resources, which includes the parameters like bandwidth, delay, jitter etc. This paper addresses guaranteed QoS in a Bluetooth scatternet by considering mainly two constraints namely Packet Loss and Waiting time .The above two constraints are met in a Bluetooth scatternet under high traffic congestion, which increases packet delay and causes channel wastage thereby affecting QoS. In the existing First In First Out (FIFO) scheme the slaves are served by the master in accordance with the arrival of the request offered by respective slaves in the form of 'first come first serve' technique. So a proposal to simulate a new priority based scheduling scheme like DST (Dynamic Scheduling Technique) has been implemented, which overcomes the pitfalls like packet loss, waiting time, and high congestion in the FIFO scheduling scheme. The results shows that the proposed DST scheduling that carries dynamic priorities for the requesting slaves by employing dynamic scheduling technique, which assures and guaranties the QoS parameters.